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Suárez-Pereira I, López-Martín C, Camarena-Delgado C, Llorca-Torralba M, González-Saiz F, Ruiz R, Santiago M, Berrocoso E. Nerve Injury Triggers Time-dependent Activation of the Locus Coeruleus, Influencing Spontaneous Pain-like Behavior in Rats. Anesthesiology 2024; 141:131-150. [PMID: 38602502 DOI: 10.1097/aln.0000000000005006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
BACKGROUND Dynamic changes in neuronal activity and in noradrenergic locus coeruleus (LC) projections have been proposed during the transition from acute to chronic pain. Thus, the authors explored the cellular cFos activity of the LC and its projections in conjunction with spontaneous pain-like behavior in neuropathic rats. METHODS Tyrosine hydroxylase:Cre and wild-type Long-Evans rats, males and females, were subjected to chronic constriction injury (CCI) for 2 (short-term, CCI-ST) or 30 days (long-term, CCI-LT), evaluating cFos and Fluoro-Gold expression in the LC, and its projections to the spinal cord (SC) and rostral anterior cingulate cortex (rACC). These tests were carried out under basal conditions (unstimulated) and after noxious mechanical stimulation. LC activity was evaluated through chemogenetic and pharmacologic approaches, as were its projections, in association with spontaneous pain-like behaviors. RESULTS CCI-ST enhanced basal cFos expression in the LC and in its projection to the SC, which increased further after noxious stimulation. Similar basal activation was found in the neurons projecting to the rACC, although this was not modified by stimulation. Strong basal cFos expression was found in CCI-LT, specifically in the projection to the rACC, which was again not modified by stimulation. No cFos expression was found in the CCI-LT LCipsilateral (ipsi)/contralateral (contra)→SC. Chemogenetics showed that CCI-ST is associated with greater spontaneous pain-like behavior when the LCipsi is blocked, or by selectively blocking the LCipsi→SC projection. Activation of the LCipsi or LCipsi/contra→SC dampened pain-like behavior. Moreover, Designer Receptor Exclusively Activated by Designer Drugs (DREADDs)-mediated inactivation of the CCI-ST LCipsi→rACC or CCI-LT LCipsi/contra→rACC pathway, or intra-rACC antagonism of α-adrenoreceptors, also dampens pain-like behavior. CONCLUSIONS In the short term, activation of the LC after CCI attenuates spontaneous pain-like behaviors via projections to the SC while increasing nociception via projections to the rACC. In the long term, only the projections from the LC to the rACC contribute to modulate pain-like behaviors in this model. EDITOR’S PERSPECTIVE
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Affiliation(s)
- Irene Suárez-Pereira
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| | - Carolina López-Martín
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| | - Carmen Camarena-Delgado
- Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain; IRCCS Humanitas Research Hospital, Milan, Italy; Institute of Neuroscience (IN-CNR), National Research Council of Italy, Milan, Italy
| | - Meritxell Llorca-Torralba
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Cell Biology and Histology, University of Cádiz, Cádiz, Spain
| | - Francisco González-Saiz
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Community Mental Health Unit of Villamartin, University Hospital of Jerez de la Frontera, Cádiz, Spain
| | - Rocío Ruiz
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Institute of Biomedicine of Sevilla (IBiS) - University Hospital Virgen del Rocío/CSIC/University of Sevilla, Sevilla, Spain
| | - Martiniano Santiago
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Institute of Biomedicine of Sevilla (IBiS) - University Hospital Virgen del Rocío/CSIC/University of Sevilla, Sevilla, Spain
| | - Esther Berrocoso
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
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Su TF, Hamilton JD, Guo Y, Potas JR, Shivdasani MN, Moalem-Taylor G, Fridman GY, Aplin FP. Peripheral direct current reduces naturally evoked nociceptive activity at the spinal cord in rodent models of pain. J Neural Eng 2024; 21:026044. [PMID: 38579742 DOI: 10.1088/1741-2552/ad3b6c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 04/05/2024] [Indexed: 04/07/2024]
Abstract
Objective.Electrical neuromodulation is an established non-pharmacological treatment for chronic pain. However, existing devices using pulsatile stimulation typically inhibit pain pathways indirectly and are not suitable for all types of chronic pain. Direct current (DC) stimulation is a recently developed technology which affects small-diameter fibres more strongly than pulsatile stimulation. Since nociceptors are predominantly small-diameter Aδand C fibres, we investigated if this property could be applied to preferentially reduce nociceptive signalling.Approach.We applied a DC waveform to the sciatic nerve in rats of both sexes and recorded multi-unit spinal activity evoked at the hindpaw using various natural stimuli corresponding to different sensory modalities rather than broad-spectrum electrical stimulus. To determine if DC neuromodulation is effective across different types of chronic pain, tests were performed in models of neuropathic and inflammatory pain.Main results.We found that in both pain models tested, DC application reduced responses evoked by noxious stimuli, as well as tactile-evoked responses which we suggest may be involved in allodynia. Different spinal activity of different modalities were reduced in naïve animals compared to the pain models, indicating that physiological changes such as those mediated by disease states could play a larger role than previously thought in determining neuromodulation outcomes.Significance.Our findings support the continued development of DC neuromodulation as a method for reduction of nociceptive signalling, and suggests that it may be effective at treating a broader range of aberrant pain conditions than existing devices.
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Affiliation(s)
- Tom F Su
- School of Biomedical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Jack D Hamilton
- School of Biomedical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Yiru Guo
- School of Biomedical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Jason R Potas
- School of Biomedical Sciences, University of New South Wales, Sydney, New South Wales, Australia
- Eccles Institute, John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Mohit N Shivdasani
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, New South Wales, Australia
| | - Gila Moalem-Taylor
- School of Biomedical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Gene Y Fridman
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States of America
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - Felix P Aplin
- School of Biomedical Sciences, University of New South Wales, Sydney, New South Wales, Australia
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Norris MR, Kuo CC, Kim JR, Dunn SS, Borges G, Thang LV, McCall JG. Endogenous opioids gate the locus coeruleus pain generator. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.20.562785. [PMID: 37961541 PMCID: PMC10634678 DOI: 10.1101/2023.10.20.562785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The locus coeruleus (LC) plays a paradoxical role in chronic pain. Although largely known as a potent source of endogenous analgesia, increasing evidence suggests injury can transform the LC into a chronic pain generator. We sought to clarify the role of this system in pain. Here, we show optogenetic inhibition of LC activity is acutely antinociceptive. Following long-term spared nerve injury, the same LC inhibition is analgesic - further supporting its pain generator function. To identify inhibitory substrates that may naturally serve this function, we turned to endogenous LC mu opioid receptors (LC-MOR). These receptors provide powerful LC inhibition and exogenous activation of LC-MOR is antinociceptive. We therefore hypothesized that endogenous LC-MOR-mediated inhibition is critical to how the LC modulates pain. Using cell type-selective conditional knockout and rescue of LC-MOR receptor signaling, we show these receptors bidirectionally regulate thermal and mechanical hyperalgesia - providing a functional gate on the LC pain generator.
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Affiliation(s)
- Makenzie R. Norris
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Chao-Cheng Kuo
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Jenny R. Kim
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Samantha S. Dunn
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Gustavo Borges
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Loc V. Thang
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Jordan G. McCall
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
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Alotaibi G, Khan A, Ronan PJ, Lutfy K, Rahman S. Glial Glutamate Transporter Modulation Prevents Development of Complete Freund's Adjuvant-Induced Hyperalgesia and Allodynia in Mice. Brain Sci 2023; 13:807. [PMID: 37239279 PMCID: PMC10216248 DOI: 10.3390/brainsci13050807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/12/2023] [Accepted: 05/13/2023] [Indexed: 05/28/2023] Open
Abstract
Glial glutamate transporter (GLT-1) modulation in the hippocampus and anterior cingulate cortex (ACC) is critically involved in nociceptive pain. The objective of the study was to investigate the effects of 3-[[(2-methylphenyl) methyl] thio]-6-(2-pyridinyl)-pyridazine (LDN-212320), a GLT-1 activator, against microglial activation induced by complete Freund's adjuvant (CFA) in a mouse model of inflammatory pain. Furthermore, the effects of LDN-212320 on the protein expression of glial markers, such as ionized calcium-binding adaptor molecule 1 (Iba1), cluster of differentiation molecule 11b (CD11b), mitogen-activated protein kinases (p38), astroglial GLT-1, and connexin 43 (CX43), were measured in the hippocampus and ACC following CFA injection using the Western blot analysis and immunofluorescence assay. The effects of LDN-212320 on the pro-inflammatory cytokine interleukin-1β (IL-1β) in the hippocampus and ACC were also assessed using an enzyme-linked immunosorbent assay. Pretreatment with LDN-212320 (20 mg/kg) significantly reduced the CFA-induced tactile allodynia and thermal hyperalgesia. The anti-hyperalgesic and anti-allodynic effects of LDN-212320 were reversed by the GLT-1 antagonist DHK (10 mg/kg). Pretreatment with LDN-212320 significantly reduced CFA-induced microglial Iba1, CD11b, and p38 expression in the hippocampus and ACC. LDN-212320 markedly modulated astroglial GLT-1, CX43, and, IL-1β expression in the hippocampus and ACC. Overall, these results suggest that LDN-212320 prevents CFA-induced allodynia and hyperalgesia by upregulating astroglial GLT-1 and CX43 expression and decreasing microglial activation in the hippocampus and ACC. Therefore, LDN-212320 could be developed as a novel therapeutic drug candidate for chronic inflammatory pain.
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Affiliation(s)
- Ghallab Alotaibi
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007, USA
| | - Amna Khan
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007, USA
| | - Patrick J. Ronan
- Research Service, Sioux Falls VA Healthcare System, Sioux Falls, SD 57105, USA
- Department of Psychiatry and Basic Biomedical Sciences, University of South Dakota Sanford School of Medicine, Sioux Falls, SD 57105, USA
| | - Kabirullah Lutfy
- College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Shafiqur Rahman
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007, USA
- Research Service, Sioux Falls VA Healthcare System, Sioux Falls, SD 57105, USA
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5
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Xie S, Xie M, Shen Y, Cheng D. Gabapentin for chronic refractory cough: A system review and meta-analysis. Heliyon 2023; 9:e15579. [PMID: 37131438 PMCID: PMC10149207 DOI: 10.1016/j.heliyon.2023.e15579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/11/2023] [Accepted: 04/14/2023] [Indexed: 05/04/2023] Open
Abstract
Objective To evaluate the efficacy and safety of gabapentin in the treatment of chronic refractory cough by Meta-Analysis. Methods Literatures were retrieved from PubMed, Embase (OvidIP), Cochrane Library, CNKI, VIP, Wanfang Database and China Biomedical Management System and eligible prospective studies were screened. Data were extracted and analyzed by using RevMan 5.4.1 software. Results Six articles (2 RCTs and 4 prospective studies) with 536 participants were finally included. Meta-analysis showed that gabapentin was better than placebo in cough-specific quality of life (LCQ score, MD = 4.02, 95%CI [3.26,4,78], Z = 10.34, P < 0.00001), cough severity (VAS score, MD = -29.36, 95% CI (-39.46, -19.26), Z = 5.7, P < 0.00001), cough frequency (MD = -29.87, 95% CI [- 43.84, -15.91], Z = 4.19, P < 0.0001) and therapeutic efficacy (RR = 1.37,95%CI [1.13,1.65], Z = 3.27, P = 0.001), and equal in safety (RR = 1.32,95%CI [0.47,3.7], Z = 0.53, P = 0.59). Gabapentin was similar to other neuromodulators in therapeutic efficacy (RR = 1.07,95%CI [0.87,1.32], Z = 0.64, P = 0.52), but its safety was better. Conclusion Gabapentin is effective in the treatment of chronic refractory cough in both subjective and objective evaluations, and its safety is better than other neuromodulators.
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Affiliation(s)
- Sheng Xie
- Department of Pulmonary and Critical Care Medicine, Chengdu First People's Hospital, Sichuan, China
| | - Meiling Xie
- Department of Traditional Chinese Medicine, Sichuan Electric Power Hospital, Sichuan, China
| | - Yongchun Shen
- Department of Pulmonary and Critical Care Medicine, West China Hospital, Sichuan University, Sichuan, China
| | - Deyun Cheng
- Department of Pulmonary and Critical Care Medicine, West China Hospital, Sichuan University, Sichuan, China
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6
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Russo M, Graham B, Santarelli DM. Gabapentin-Friend or foe? Pain Pract 2023; 23:63-69. [PMID: 36300903 PMCID: PMC10092611 DOI: 10.1111/papr.13165] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/19/2022] [Indexed: 01/11/2023]
Abstract
BACKGROUND Gabapentin is a recommended first-line agent for treating neuropathic pain; however, its efficacy rate is reportedly low, and the risk of adverse events is high. A plausible explanation for this lies with its wide range of actions, the entirety of which have yet to be fully elucidated. METHODS A review of the literature was conducted on gabapentin's known and proposed analgesic mechanisms of action, as well as potentially opposing or detrimental actions. RESULTS Gabapentin's classical analgesic mechanisms involve direct attenuation of excitatory neurotransmission in the spinal cord via inhibition of neuronal ion channels, while indirect mechanisms include descending inhibition and block of injury-evoked synaptogenesis. Glial effects have also been reported; however, whether they are neuroprotective or detrimental is unknown. Furthermore, data from animal models do not reflect clinical outcomes. CONCLUSIONS Gabapentin's clinical use should be reconsidered according to the net effects of its numerous assumed actions, including the tripartite synapse and oligodendrocyte effects. Whether it is doing more harm than good, especially in the scenarios of incomplete or loss of response, warrants consideration when prescribing gabapentin.
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Affiliation(s)
- Marc Russo
- Hunter Pain Specialists, Broadmeadow, New South Wales, Australia.,Genesis Research Services, Broadmeadow, New South Wales, Australia.,School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Brett Graham
- School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
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Halili A. Temporal model for central sensitization: A hypothesis for mechanism and treatment using systemic manual therapy, a focused review. MethodsX 2022; 10:101942. [PMID: 36570602 PMCID: PMC9772546 DOI: 10.1016/j.mex.2022.101942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
The purpose of this focused review is to develop a consolidated hypothesis as to the causes and mechanisms of central sensitization and a related model for a treatment approach using Systemic Manual Therapy (SMT). The key to understanding central sensitization is a firm grasp on structure and function of the Locus-coeruleus noradrenaline system (LC-NA). This system uses an elaborate switching mechanism to control the level and rate of activation of multiple systems. This review evaluates the mechanisms and temporal relationships behind four components: salient stimuli, threat coding, aberrant afferent input, and oxidative stress. The five-stage temporal model for central sensitization includes phasic activation of the LC-NA system, salient stimuli, threat coding of salient stimuli, central sensitization, and neural degeneration. The three components of treatment include temporarily reducing afferent visceral input, shifting humoral inflammatory activity away from the brain and outside the body, and reducing oxidative stress by making oxygenated blood more available around the LC and other stressed areas in the brain. The SMT protocols that could help in reduction of visceral afferent input are GUOU, Barral and LAUG. Protocols that should shift humoral inflammatory activity away from the brain or completely out of the body include UD and DCS. One protocol that can potentially reduce oxidative stress by making oxygenated blood more available around the LC is CCCV. Future research and hypothesis-testing strategies as well as limitations are further discussed.
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Temmermand R, Barrett JE, Fontana ACK. Glutamatergic systems in neuropathic pain and emerging non-opioid therapies. Pharmacol Res 2022; 185:106492. [PMID: 36228868 PMCID: PMC10413816 DOI: 10.1016/j.phrs.2022.106492] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 01/14/2023]
Abstract
Neuropathic pain, a disease of the somatosensory nervous system, afflicts many individuals and adequate management with current pharmacotherapies remains elusive. The glutamatergic system of neurons, receptors and transporters are intimately involved in pain but, to date, there have been few drugs developed that therapeutically modulate this system. Glutamate transporters, or excitatory amino acid transporters (EAATs), remove excess glutamate around pain transmitting neurons to decrease nociception suggesting that the modulation of glutamate transporters may represent a novel approach to the treatment of pain. This review highlights and summarizes (1) the physiology of the glutamatergic system in neuropathic pain, (2) the preclinical evidence for dysregulation of glutamate transport in animal pain models, and (3) emerging novel therapies that modulate glutamate transporters. Successful drug discovery requires continuous focus on basic and translational methods to fully elucidate the etiologies of this disease to enable the development of targeted therapies. Increasing the efficacy of astrocytic EAATs may serve as a new way to successfully treat those suffering from this devastating disease.
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Affiliation(s)
- Rhea Temmermand
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - James E Barrett
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Andréia C K Fontana
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
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Paul B, Sribhashyam S, Majumdar S. Opioid signaling and design of analgesics. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 195:153-176. [PMID: 36707153 PMCID: PMC10325139 DOI: 10.1016/bs.pmbts.2022.06.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Clinical treatment of acute to severe pain relies on the use of opioids. While their potency is significant, there are considerable side effects that can negatively affect patients. Their rise in usage has correlated with the current opioid epidemic in the United States, which has led to more than 70,000 deaths per year (Volkow and Blanco, 2021). Opioid-related drug development aims to make target compounds that show strong potency but with diminished side effects. Research into pharmaceuticals that could act as potential alternatives to current pains medications has relied on mechanistic insights of opioid receptors, a class of G-protein coupled receptors (GPCRs), and biased agonism, a common phenomenon among pharmaceutical compounds where downstream effects can be altered at the same receptor via different agonists. Opioids function typically by binding to an active site on the extracellular portion of opioid receptors. Once activated, the opioid receptor initiates a G-protein signaling pathway and/or the β-arrestin2 pathway. The proposed concept for the development of safe analgesics around mu and kappa opioid receptor subtypes has focused on not recruiting β-arrestin2 (biased agonism) and/or having low efficacy at the receptor (partial agonism). By altering chemical motifs on a common scaffold, chemists can take advantage of biased agonism as well as create compounds with low intrinsic efficacy for the desired treatments. This review will focus on ligands with bias profile, signaling aspects of the receptor and probe into the structural basis of receptor that leads to bias and/or partial agonism.
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Affiliation(s)
- Barnali Paul
- Center for Clinical Pharmacology, University of Health Sciences & Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, United States
| | - Sashrik Sribhashyam
- Center for Clinical Pharmacology, University of Health Sciences & Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, United States
| | - Susruta Majumdar
- Center for Clinical Pharmacology, University of Health Sciences & Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, United States.
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Yoon SY, Roh DH, Yeo JH, Woo J, Han SH, Kim KS. Analgesic Efficacy of α 2 Adrenergic Receptor Agonists Depends on the Chronic State of Neuropathic Pain: Role of Regulator of G Protein Signaling 4. Neuroscience 2020; 455:177-194. [PMID: 33359660 DOI: 10.1016/j.neuroscience.2020.12.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 12/12/2020] [Accepted: 12/14/2020] [Indexed: 12/16/2022]
Abstract
The analgesic effect of alpha-2 adrenergic receptor (α2AR) agonists, which relieve chronic neuropathic pain, is highly variable among individuals. Here, we used a mouse model of spared nerve injury (SNI) to show that treatment time after the establishment of neuropathic pain was important for the variability in the analgesic efficacy of α2AR agonists, which was related to the activity of regulator of G-protein signaling protein 4 (RGS4). Intrathecal treatment with α2AR agonists, clonidine (0.1-1 nmol) or dexmedetomidine (0.3-1 nmol), relieved mechanical allodynia and thermal hyperalgesia on postoperative day (POD) 14, but their efficacy was weaker on POD28 and absent on POD56. The RGS4 level of plasma membrane was increased on POD56 compared to that on POD14. Moreover, in RGS4-deficient or RGS4 inhibitor (CCG50014)-treated mice, the analgesic effect of the α2AR agonists was conserved even on POD56. The increased plasma membrane RGS4 expression and the reduced level of active Gαi after clonidine injection on POD56 were completely restored by CCG50014. Higher doses of clonidine (10 nmol) and dexmedetomidine (3 nmol) relieved neuropathic pain on POD56 but were accompanied with serious side effects. Whereas, the coadministration of CCG50014 with clonidine (1 nmol) or dexmedetomidine (1 nmol) did not cause side effects. These findings demonstrated that SNI-induced increase in plasma membrane RGS4 expression was associated with low efficacy of α2AR agonists in a model of persistent, chronic neuropathic pain. Furthermore, α2AR agonist administration together with RGS4-targeted intervention represents a novel strategy for the treatment of neuropathic pain to overcome dose-limiting side effects.
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Affiliation(s)
- Seo-Yeon Yoon
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; College of Korean Medicine, Dongshin University, Gunjae Road 185, Naju-si, Jeonnam 58245, Republic of Korea.
| | - Dae-Hyun Roh
- Department of Oral Physiology, School of Dentistry, Kyung Hee University, Seoul 02454, Republic of Korea
| | - Ji-Hee Yeo
- Department of Oral Physiology, School of Dentistry, Kyung Hee University, Seoul 02454, Republic of Korea
| | - Jiwan Woo
- Research Animal Resource Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Se Hee Han
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Key-Sun Kim
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Research Animal Resource Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea.
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11
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Tsuji O, Kosugi S, Suzuki S, Nori S, Nagoshi N, Okada E, Fujita N, Yagi M, Nakamura M, Matsumoto M, Watanabe K. Effectiveness of Duloxetine for Postsurgical Chronic Neuropathic Disorders after Spine and Spinal Cord Surgery. Asian Spine J 2020; 15:650-658. [PMID: 33189110 PMCID: PMC8561146 DOI: 10.31616/asj.2020.0191] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/20/2020] [Indexed: 12/26/2022] Open
Abstract
Study Design This is a retrospective observational study with an outpatient setting. Purpose This study aimed to describe the effects of duloxetine (DLX) administration for postsurgical chronic neuropathic disorders (both pain and numbness) following spinal surgery in patients without depression. Overview of Literature Although several reports indicated the potential of DLX to effectively treat postoperative symptoms as a perioperative intervention, there have been no reports of its positive effect on postsurgical chronic neuropathic disorders. Methods A total of 24 patients with postsurgical chronic pain and/or numbness Numeric Rating Scale (NRS) scores of ≥4 were enrolled. All patients underwent spine or spinal cord surgery at Keio University Hospital and received daily administration of DLX for more than 3 months. The mean postoperative period before the first administration of DLX was 35.5±57.0 months. DLX was administered for more than 3 months at a dose of 20, 40, or 60 mg/day, and the degree of pain and numbness was evaluated using the NRS before administration and 3 months after administration. Effectiveness was defined as more than a 2-point decrease in the NRS score following administration. Results In terms of the type of symptoms, 15 patients experienced only numbness, eight experienced both pain and numbness, and one experienced only pain. Of the 24 patients, 19 achieved effective relief with DLX. DLX was effective for all patients with postsurgical chronic pain (n=9), and it reduced postsurgical chronic numbness in 18 of 23 patients. No significant difference was observed in background spinal disorders. DLX was not effective for five patients who complained only of postsurgical chronic numbness. Conclusions This study reports the effectiveness of DLX for postsurgical chronic neuropathic disorders. Although DLX reduced postsurgical chronic pain (efficacy rate=100%) and numbness (78.3%) in certain patients, further investigation is needed to determine its optimal use.
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Affiliation(s)
- Osahiio Tsuji
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Shizuko Kosugi
- Department of Anesthesiology, Keio University School of Medicine, Tokyo, Japan
| | - Satoshi Suzuki
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Satoshi Nori
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Narihito Nagoshi
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Eijiro Okada
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Nobuyuki Fujita
- Department of Orthopaedic Surgery, Fujita Health University, Aichi, Japan
| | - Mitsuru Yagi
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Masaya Nakamura
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Morio Matsumoto
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Kota Watanabe
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
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12
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Muralidharan A, Sotocinal SG, Austin JS, Mogil JS. The influence of aging and duration of nerve injury on the antiallodynic efficacy of analgesics in laboratory mice. Pain Rep 2020; 5:e824. [PMID: 32903926 PMCID: PMC7447376 DOI: 10.1097/pr9.0000000000000824] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/21/2020] [Accepted: 04/25/2020] [Indexed: 11/26/2022] Open
Abstract
INTRODUCTION Increasing attention is being paid to the effects of organismic factors like age on pain sensitivity. However, very little data exist on this topic using modern algesiometric assays and measures in laboratory rodents. OBJECTIVES We investigated the effect of age and duration of nerve injury on baseline mechanical thresholds, neuropathic allodynia, and the antiallodynic and analgesic efficacy of 4 systemically administered analgesics: amitriptyline, diclofenac, morphine, and pregabalin. METHODS Mice of both sexes and 3 conditions were compared: Young-Young, in which baseline testing (von Frey thresholds), the injury producing neuropathic pain (spared nerve injury [SNI]) and subsequent drug testing occurred while mice were young (8-10 weeks); Young-Old, in which mice received the nerve injury while young but were tested for drug efficacy over 10 months later; and Old-Old, in which both the nerve injury and drug testing occurred at approximately 1 year of age. RESULTS Old-Old mice were found to display higher baseline mechanical sensitivity than other groups. No group differences were seen in SNI-induced allodynia in males; female Young-Old mice were found to display greatly reduced allodynia. With respect to drug efficacy, no differences among conditions were observed for amitriptyline, diclofenac, or morphine. For pregabalin, however, Young-Old mice displayed significantly reduced antiallodynia, and the drug was completely ineffective in Old-Old mice. CONCLUSION Novel findings include the apparent remission of SNI-induced allodynia in female mice 10 months after injury and reduced pregabalin antiallodynic effects produced by both the passage of time after nerve injury and aging.
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Affiliation(s)
- Arjun Muralidharan
- Department of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
| | - Susana G. Sotocinal
- Department of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
| | | | - Jeffrey S. Mogil
- Department of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
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13
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Chincholkar M. Gabapentinoids: pharmacokinetics, pharmacodynamics and considerations for clinical practice. Br J Pain 2020; 14:104-114. [PMID: 32537149 DOI: 10.1177/2049463720912496] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The gabapentinoids are often recommended as first-line treatments for the management of neuropathic pain. The differing pharmacodynamic and pharmacokinetic profiles can have implications for clinical practice. This article has summarised these key differences. In addition to their use in managing neuropathic pain, gabapentinoids are increasingly being used for off-label conditions despite the lack of evidence. Prescription rates for off-label conditions have overtaken that for on-label use. Similarly, the use of gabapentinoids in the perioperative period is now embedded in clinical practice despite conflicting evidence. This article summarises the risks associated with this increasing use. There is increasing evidence of the potential to cause harm in vulnerable populations such as the elderly and increasing prevalence of abuse. The risk of respiratory depression in combination with opioids is of particular concern in the context of the current opioid crisis. This article describes the practical considerations involved that might help guide appropriate prescribing practices.
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14
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Kato D, Suto T, Obata H, Saito S. Spinal Activation of Tropomyosin Receptor Kinase-B Recovers the Impaired Endogenous Analgesia in Neuropathic Pain Rats. Anesth Analg 2020; 129:578-586. [PMID: 29933273 DOI: 10.1213/ane.0000000000003592] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Although endogenous analgesia plays an important role in controlling pain states, chronic pain patients exhibit decreased endogenous analgesia compared to healthy individuals. In rats, noxious stimulus-induced analgesia (NSIA), which is an indicator of endogenous analgesia, diminished 6 weeks after spinal nerve ligation (SNL6W). A recent study in rats with deleted noradrenergic fibers demonstrated that the noradrenergic fibers were essential to NSIA. It has also been reported that brain-derived neurotrophic factor increased spinal noradrenergic fibers. Therefore, this study examined the effect of TrkB activation, which is the receptor for brain-derived neurotrophic factor, on impaired NSIA in SNL6W rats. In addition, we also examined the effect of endogenous analgesia on acute incisional pain. METHODS After 5 daily intraperitoneal injections of 7,8-dihydroxyflavone (7,8-DHF, TrkB agonist, 5 mg/kg), NSIA was examined by measuring the withdrawal threshold increment in the left (contralateral to nerve ligation) hindpaw at 30 minutes after capsaicin injection (250 μg) in the forepaw. K252a (TrkB antagonist, 2 μg) was administrated intrathecally for 5 days. Idazoxan (α2 adrenoceptor antagonist, 30 μg), atropine (muscarinic antagonist, 30 μg), and propranolol (nonselective β adrenoceptor antagonist, 30 μg) were administered intrathecally for 15 minutes before capsaicin injection. Microdialysis and immunohistochemistry were performed to examine the noradrenergic plasticity in the spinal dorsal horn. A hindpaw incision was performed on the left (contralateral to nerve ligation) hindpaw. Data were analyzed by 1-way analyses of variance or 2-way repeated-measures 1-way analysis of variance followed by a Student t test with Bonferroni correction. RESULTS Five daily intraperitoneal injections of 7,8-DHF restored the attenuated NSIA in SNL6W rats (n = 7, P = .002; estimated treatment effect [95% CI]: 62.9 [27.0-98.7] g), with this effect blocked by 5 daily intrathecal coadministrations of K252a (n = 6, P < .001; -57.8 [-78.3 to -37.2] g). This effect was also inhibited by a single intrathecal administration of idazoxan (n = 8, P < .001; -61.6 [-92.4 to -30.9] g) and atropine (n = 8, P = .003; -52.6 [-73.3 to -31.9] g), but not by propranolol. Furthermore, 7,8-DHF increased the noradrenergic fiber in the spinal dorsal horn and the noradrenaline release in response to the capsaicin injection in the forepaw in SNL6W rats. In addition, repeated injections of 7,8-DHF prevented delayed recovery from incisional pain in SNL6W rats. CONCLUSIONS Spinal activation of TrkB may recover the attenuated endogenous analgesia by improving the adrenergic plasticity, thereby leading to prevention of pain prolongation after surgery.
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Affiliation(s)
- Daiki Kato
- From the Department of Anesthesiology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Takashi Suto
- From the Department of Anesthesiology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Hideaki Obata
- Department of Anesthesiology and Center of Pain Management, Fukushima Medical University, Fukushima, Japan
| | - Shigeru Saito
- From the Department of Anesthesiology, Gunma University Graduate School of Medicine, Maebashi, Japan
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15
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Li Q, Lu J, Zhou X, Chen X, Su D, Gu X, Yu W. High-Voltage-Activated Calcium Channel in the Afferent Pain Pathway: An Important Target of Pain Therapies. Neurosci Bull 2019; 35:1073-1084. [PMID: 31065935 PMCID: PMC6864004 DOI: 10.1007/s12264-019-00378-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 12/24/2018] [Indexed: 12/31/2022] Open
Abstract
High-voltage-activated (HVA) Ca2+ channels are widely expressed in the nervous system. They play an important role in pain conduction by participating in various physiological processes such as synaptic transmission, changes in synaptic plasticity, and neuronal excitability. Available evidence suggests that the HVA channel is an important therapeutic target for pain management. In this review, we summarize the changes in different subtypes of HVA channel during pain and present the currently available evidence from the clinical application of HVA channel blockers. We also review novel drugs in various phases of development. Moreover, we discuss the future prospects of HVA channel blockers in order to promote "bench-to-bedside" translation.
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Affiliation(s)
- Qi Li
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Jian Lu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
- Department of Anesthesiology, The Second Affiliated Hospital of Jiaxing University, Jiaxing, 314000, China
| | - Xiaoxin Zhou
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Xuemei Chen
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Diansan Su
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Xiyao Gu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China.
| | - Weifeng Yu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China.
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16
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Hayashida KI, Eisenach JC, Kawatani M, Martin TJ. Peripheral nerve injury in rats induces alternations in choice behavior associated with food reinforcement. J Physiol Sci 2019; 69:769-777. [PMID: 31267368 PMCID: PMC10717269 DOI: 10.1007/s12576-019-00693-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 06/25/2019] [Indexed: 11/24/2022]
Abstract
Operant methods that allow animals to avoid painful stimuli are interpreted to assess the aversive quality of pain; however, such measurements require investigator-initiated stimuli to animals. Here we developed a shuttle maze test to repeatedly assess activity associated nociception without forced stimulation. Rats ambulate back and forth between two treat feeders by taking either a short route with a prickly surfaced arch or a longer route with a smooth floor. L5-L6 spinal nerve ligation (SNL) reduced the preference for the short route with the arch, correlated with hypersensitivity in the hind paw. Oral gabapentin restored the short route preference and reduced hypersensitivity in SNL rats, and blockade of spinal α2-adrenoceptors reduced gabapentin's effects on hypersensitivity but not on preference index. These results suggest that SNL injury alters behavior in the shuttle maze test and that the shuttle maze test shows comparable results to reflexive hypersensitivity after SNL in magnitude and response to gabapentin.
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Affiliation(s)
- Ken-Ichiro Hayashida
- Department of Neurophysiology, Akita University School of Medicine, Akita, 010-8543, Japan.
| | - James C Eisenach
- Pain Mechanisms Laboratory, Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, NC, 27157, USA
| | - Masahito Kawatani
- Department of Neurophysiology, Akita University School of Medicine, Akita, 010-8543, Japan
| | - Thomas J Martin
- Pain Mechanisms Laboratory, Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, NC, 27157, USA
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17
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Deng HS, Xu LS, Ni HD, Wang TT, Liu MJ, Yang MX, Shen H, Pan H, Yao M. Proteomic profiling reveals Arl6ip-1 as a candidate target in cancer-induced bone pain rat model after oxycodone treatment. Neurosci Lett 2019; 699:151-159. [PMID: 30708128 DOI: 10.1016/j.neulet.2019.01.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 01/10/2019] [Accepted: 01/27/2019] [Indexed: 10/27/2022]
Abstract
Treatment of cancer-induced bone pain (CIBP) is challenging in clinics. Oxycodone is used to treat CIBP. However, the lack of understanding of the mechanism of CIBP limits the application of oxycodone. In this study, proteomic profiling of oxycodone-treated spinal dorsal cord of rats with CIBP was performed. Briefly, a total of 3519 proteins were identified in the Sham group; 3505 proteins in the CIBP group; and 3530 proteins in the CIBP-OXY treatment group. The 2-fold cut-off value was used as the differential protein standard for abundance reduction or increase (p < 0.05). Significant differences were found in the abundance of 16 proteins between Sham and CIBP group; 11 proteins in the CIBP group had increased abundance while 5 proteins had reduced abundance. Furthermore, fifteen proteins with differential abundance were identified between the CIBP group and the OXY group. Compared with the CIBP group, there were six increased abundances and nine reduced abundances in the OXY group. In addition, a reduced expression of ADP-ribosylation factor-like 6 binding factor 1 (Arl6ip-1), an endoplasmic reticulum protein that has an important role in cell conduction and material transport, was found in the CIBP group compared with the Sham group. Its expression increased after the administration of OXY. Proteomics results were further verified by Western-blot. Fluorescent staining revealed that Arl6ip-1 co-localized with spinal dorsal horn neurons, but not with astrocytes or microglia. Based on the observed results, we believe that Arl6ip-1 may be a potential drug target for OXY treatment of CIBP rats.
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Affiliation(s)
- Hou-Sheng Deng
- Department of Anesthesiology and Pain Medicine, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Long-Sheng Xu
- Department of Central Laboratory, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Hua-Dong Ni
- Department of Anesthesiology and Pain Medicine, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Ting-Ting Wang
- Department of Anesthesiology and Pain Medicine, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Ming-Juan Liu
- Department of Anesthesiology and Pain Medicine, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Mao-Xian Yang
- Department of Intensive Care Unit, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Hui Shen
- Department of Central Laboratory, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Huan Pan
- Department of Central Laboratory, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China
| | - Ming Yao
- Department of Anesthesiology and Pain Medicine, The First Affiliated Hospital of Jiaxing University, Jiaxing, 314001, China.
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18
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Castany S, Codony X, Zamanillo D, Merlos M, Verdú E, Boadas-Vaello P. Repeated Sigma-1 Receptor Antagonist MR309 Administration Modulates Central Neuropathic Pain Development After Spinal Cord Injury in Mice. Front Pharmacol 2019; 10:222. [PMID: 30967775 PMCID: PMC6439356 DOI: 10.3389/fphar.2019.00222] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 02/22/2019] [Indexed: 12/19/2022] Open
Abstract
Up to two-thirds of patients affected by spinal cord injury (SCI) develop central neuropathic pain (CNP), which has a high impact on their quality of life. Most of the patients are largely refractory to current treatments, and new pharmacological strategies are needed. Recently, it has been shown that the acute administration of the σ1R antagonist MR309 (previously developed as E-52862) at 28 days after spinal cord contusion results in a dose-dependent suppression of both mechanical allodynia and thermal hyperalgesia in wild-type CD-1 Swiss female mice. The present work was addressed to determine whether MR309 might exert preventive effects on CNP development by repeated administration during the first week after SCI in mice. To this end, the MR309 (16 or 32 mg/kg i.p.) modulation on both thermal hyperalgesia and mechanical allodynia development were evaluated weekly up to 28 days post-injury. In addition, changes in pro-inflammatory cytokine (TNF-α, IL-1β) expression and both the expression and activation (phosphorylation) of the N-methyl-D-aspartate receptor subunit 2B (NR2B-NMDA) and extracellular signal-regulated kinases (ERK1/2) were analyzed. The repeated treatment of SCI-mice with MR309 resulted in significant pain behavior attenuation beyond the end of the administration period, accompanied by reduced expression of central sensitization-related mechanistic correlates, including extracellular mediators (TNF-α and IL-1β), membrane receptors/channels (NR2B-NMDA) and intracellular signaling cascades (ERK/pERK). These findings suggest that repeated MR309 treatment after SCI may be a suitable pharmacologic strategy to modulate SCI-induced CNP development.
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Affiliation(s)
- Sílvia Castany
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Universitat de Girona, Girona, Spain
| | - Xavier Codony
- Esteve Pharmaceuticals, Drug Discovery and Preclinical Development, Parc Científic de Barcelona, Barcelona, Spain
| | - Daniel Zamanillo
- Esteve Pharmaceuticals, Drug Discovery and Preclinical Development, Parc Científic de Barcelona, Barcelona, Spain
| | - Manuel Merlos
- Esteve Pharmaceuticals, Drug Discovery and Preclinical Development, Parc Científic de Barcelona, Barcelona, Spain
| | - Enrique Verdú
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Universitat de Girona, Girona, Spain
| | - Pere Boadas-Vaello
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Universitat de Girona, Girona, Spain
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19
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Alles SRA, Smith PA. Comparison of ex vivo and in vitro actions of gabapentin in superficial dorsal horn and the role of extra-spinal sites of drug action. Neurosci Lett 2019; 694:148-153. [PMID: 30500395 DOI: 10.1016/j.neulet.2018.11.050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/23/2018] [Accepted: 11/26/2018] [Indexed: 10/27/2022]
Abstract
Although gabapentin (GBP) is a first-line treatment in the management of neuropathic pain, its mechanism of action is incompletely understood. We have previously shown, in rats made neuropathic following sciatic chronic constriction injury, that IP injection of 100 mg/kg GBP decreases overall excitability of spinal cord slices obtained ex vivo. Excitability was assessed using confocal imaging to monitor the amplitude of K+- induced increases in cytoplasmic Ca2+. This decrease in excitability involved a reduction in the frequency and amplitude of spontaneous EPSC's (sEPSC) in putative excitatory substantia gelatinosa neurons and an increase in sEPSC frequency in putative inhibitory neurons. We used have whole-cell recording to compare these ex vivo actions of GBP with its acute in vitro effects on spinal cord slices obtained from neuropathic but drug-free rats. While GBP (100μM) decreased sEPSC amplitude and frequency in excitatory neurons in vitro in a similar fashion to effects observed ex vivo, sEPSC frequency in inhibitory neurons was decreased in vitro rather than increased. Acute in vitro application of GBP also failed to decrease the overall excitability of slices from neuropathic animals as monitored by confocal Ca2+ imaging. Since spinal cord slices in vitro are disconnected from the periphery and higher brain centres, the GBP-induced increase in sEPSC frequency in inhibitory neurons previously reported and seen ex vivo must result from extra-spinal actions. It may be attributable to alterations in descending neurotrophic control of dorsal horn circuitry.
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Affiliation(s)
- Sascha R A Alles
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Peter A Smith
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, T6G 2H7, Canada.
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20
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Hayashida KI, Obata H. Strategies to Treat Chronic Pain and Strengthen Impaired Descending Noradrenergic Inhibitory System. Int J Mol Sci 2019; 20:ijms20040822. [PMID: 30769838 PMCID: PMC6412536 DOI: 10.3390/ijms20040822] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 02/04/2019] [Accepted: 02/12/2019] [Indexed: 12/28/2022] Open
Abstract
Gabapentinoids (gabapentin and pregabalin) and antidepressants (tricyclic antidepressants and serotonin noradrenaline reuptake inhibitors) are often used to treat chronic pain. The descending noradrenergic inhibitory system from the locus coeruleus (LC) to the dorsal horn of the spinal cord plays an important role in the analgesic mechanisms of these drugs. Gabapentinoids activate the LC by inhibiting the release of γ-aminobutyric acid (GABA) and inducing the release of glutamate, thereby increasing noradrenaline levels in the spinal cord. Antidepressants increase noradrenaline levels in the spinal cord by inhibiting reuptake, and accumulating noradrenaline inhibits chronic pain through α2-adrenergic receptors in the spinal cord. Recent animal studies, however, revealed that the function of the descending noradrenergic inhibitory system is impaired in chronic pain states. Other recent studies found that histone deacetylase inhibitors and antidepressants restore the impaired noradrenergic descending inhibitory system acting on noradrenergic neurons in the LC.
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Affiliation(s)
- Ken-Ichiro Hayashida
- Doctorial Course in Medicine, Organ Function-Oriented Medicine, Akita University Graduate School of Medicine;1-1-1, Hondo, Akita-City, Akita 010-8543, Japan.
| | - Hideaki Obata
- Center for Pain Management and Department of Anesthesiology, Fukushima Medical University; 1 Hikarigaoka, Fukushima-City, Fukushima 960-1295, Japan.
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Suto T, Kato D, Obata H, Saito S. Tropomyosin Receptor Kinase B Receptor Activation in the Locus Coeruleus Restores Impairment of Endogenous Analgesia at a Late Stage Following Nerve Injury in Rats. THE JOURNAL OF PAIN 2018; 20:600-609. [PMID: 30529695 DOI: 10.1016/j.jpain.2018.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 11/08/2018] [Accepted: 11/28/2018] [Indexed: 12/16/2022]
Abstract
A rat model of neuropathic pain at 6 weeks after spinal nerve ligation (SNL6w) exhibits both mechanical hypersensitivity and impaired noxious stimuli-induced analgesia (NSIA). Repeated treatment with antidepressants can produce antihypersensitivity and restore NSIA. To examine the involvement of a brain-derived neurotrophic factor-mediated mechanism, a tropomyosin receptor kinase B (TrkB) agonist, 7,8-dihydroxyflavone (DHF), was administered to SNL6w rats (5 mg/kg/d for 5 days). Mechanical hypersensitivity was evaluated using the von Frey filament test and paw pressure test. NSIA was examined by measuring the change in the hind paw withdrawal threshold 30 minutes after painful stimulation induced by capsaicin injection into the fore paw. Changes in the concentrations of glutamate and GABA in the locus coeruleus area were measured by in vivo microdialysis. DHF treatment did not affect mechanical hypersensitivity, although it restored NSIA by reducing GABA release in response to the fore paw capsaicin injection. DHF treatment did not alter the baseline concentration of glutamate or GABA. These findings suggest that DHF treatment restored the stimuli-response activity of the locus coeruleus without affecting the tonic activity of the locus coeruleus. The brain-derived neurotrophic factor-TkB signaling is also involved in the NSIA-restoring effect of amitriptyline. PERSPECTIVE: This article demonstrates that repeated treatment with TrkB agonist, DHF, restored endogenous analgesia. Repeated amitriptyline treatment showed similar effect via TrkB-mediated mechanisms, and the effect may be independent from the effect of antihypersensitivity. This effect of TrkB activation is promising for patients with chronic pain with impaired descending inhibition.
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Affiliation(s)
- Takashi Suto
- Department of Anesthesiology, Gunma University Graduate School of Medicine, Gunma, Japan.
| | - Daiki Kato
- Department of Anesthesiology, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Hideaki Obata
- Department of Anesthesiology and Center for Pain Management, Fukushima Medical University, Fukushima, Japan
| | - Shigeru Saito
- Department of Anesthesiology, Gunma University Graduate School of Medicine, Gunma, Japan
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22
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The onset of treatment with the antidepressant desipramine is critical for the emotional consequences of neuropathic pain. Pain 2018; 159:2606-2619. [DOI: 10.1097/j.pain.0000000000001372] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Heme oxygenase-1 inducer and carbon monoxide-releasing molecule enhance the effects of gabapentinoids by modulating glial activation during neuropathic pain in mice. Pain Rep 2018; 3:e677. [PMID: 30534628 PMCID: PMC6181470 DOI: 10.1097/pr9.0000000000000677] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 07/02/2018] [Accepted: 07/06/2018] [Indexed: 11/25/2022] Open
Abstract
Introduction Neuropathic pain is one of the most difficult-to-treat symptoms. Although gabapentinoids are classified as first-line drugs, they have only modest efficacy. Objectives The aim of this study was to investigate whether treatment with the heme oxygenase-1 (HO-1) inducer cobalt protoporphyrin IX (CoPP) or the carbon monoxide-releasing molecule tricarbonyldichlororuthenium (II) dimer (CORM-2) can enhance the antinociceptive effects produced by gabapentinoids in mice with neuropathic pain. Methods Neuropathic pain was induced by spared nerve injury (SNI) of the sciatic nerve. The mechanical threshold was tested using von Frey filaments. The expression of spinal HO-1, HO-2, the Ca2+ channel α2δ1 subunit, microglial markers, and M1 or M2 microglial markers was examined using reverse transcription polymerase chain reaction. Results Treatment with CoPP or CORM-2 alleviated mechanical allodynia induced by SNI. CoPP or CORM-2 enhanced the antiallodynic effects of gabapentinoids (pregabalin or gabapentin) during SNI-induced mechanical allodynia. HO-1 inhibitor tin protoporphyrin IX (SnPP) prevented the antiallodynic effects of gabapentinoids (pregabalin or gabapentin) during SNI-induced mechanical allodynia. CoPP or CORM-2 increased HO-1 and Ca2+ channel α2δ1 subunit gene expression and the decreased gene expression of microglial markers, M1 microglial marker, or tumor necrosis factor in the ipsilateral spinal dorsal horn of mice with SNI. SnPP prevented HO-1 induction and glial inhibition, which were produced by gabapentinoids during SNI-induced mechanical allodynia. Conclusions This study suggests that HO-1 plays crucial roles in the antiallodynic effects of gabapentinoids. Gabapentinoids attenuate the glial activation induced by SNI and some of these effects are mediated by HO-1.
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Bowen AJ, Huang TL, Nowacki AS, Trask D, Kaltenbach J, Taliercio R, Benninger MS, Milstein CF, Bryson PC. Tachyphylaxis and Dependence in Pharmacotherapy for Unexplained Chronic Cough. Otolaryngol Head Neck Surg 2018; 159:705-711. [PMID: 30016197 DOI: 10.1177/0194599818788062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Objective Unexplained chronic cough (UCC) is a perplexing condition treated with neuromodulators. Although previous literature describes the effectiveness of neuromodulators, there is little on the development of tachyphylaxis or dependence to neuromodulators over time. Our objective is to capture the experience of a large cohort of patients with UCC over an extended period, looking for these 2 phenomena. Study Design Case series with chart review. Setting Tertiary care hospital. Subjects and Methods We performed a retrospective review of patients diagnosed with UCC from 2010 to 2014. Patient outcomes were measured through percentage improvement scores. Treatment failures were attributed to no benefit, intolerable side effects, or tachyphylaxis. Tachyphylaxis was defined as the need for higher doses of medication following diminishing therapeutic benefit, while dependence was defined as a failure to stop therapy following attempted de-escalation or resurgence following drug cessation. Results Sixty-eight patients were included in the study. Tachyphylaxis was observed among 35% of patients while dependence was observed among 27% of successfully treated patients, together effecting >50% of the cohort. Sixty-eight percent of patients ultimately experienced successful treatment with neuromodulators, demonstrating strikingly distinct responses to different neuromodulator drug classes. Conclusion Tachyphylaxis and dependence occur frequently during UCC treatment and have a major impact on treatment outcomes. Patients sometimes demonstrate distinct responses to different neuromodulator classes. The majority of patients will experience successful treatment for their cough, although several trials may be required.
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Affiliation(s)
- Andrew J Bowen
- 1 Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Tiffany L Huang
- 2 School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Amy S Nowacki
- 3 Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | - Douglas Trask
- 4 Verity Health System, Los Angeles, California, USA
| | - James Kaltenbach
- 3 Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | | | | | | | - Paul C Bryson
- 6 Cleveland Clinic Head and Neck Institute, Cleveland, Ohio, USA
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Chincholkar M. Analgesic mechanisms of gabapentinoids and effects in experimental pain models: a narrative review. Br J Anaesth 2018; 120:1315-1334. [DOI: 10.1016/j.bja.2018.02.066] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 02/07/2018] [Accepted: 03/14/2018] [Indexed: 12/17/2022] Open
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Bowen AJ, Nowacki AS, Contrera K, Trask D, Kaltenbach J, Milstein CF, Adessa M, Benninger MS, Taliercio R, Bryson PC. Short- and Long-term Effects of Neuromodulators for Unexplained Chronic Cough. Otolaryngol Head Neck Surg 2018; 159:508-515. [DOI: 10.1177/0194599818768517] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Objective To evaluate the short- and long-term effects of tricyclic antidepressants (TCAs) and gabapentin in the treatment of unexplained chronic cough (UCC). Study Design Prospective cohort. Setting Tertiary care hospital. Subjects and Methods Patients seen between July 2016 and March 2017 were included following a formal workup and clinical evaluation indicative of UCC. Patients were placed on either a TCA (amitriptyline or nortriptyline) or gabapentin. Leicester Cough Questionnaire (LCQ) and percentage improvement scores were obtained prior to treatment initiation and at 2 and 6 months of neuromodulator treatment. A linear mixed model assessed the change in LCQ score between the 2 treatment time points and baseline scores. Results Twenty-eight patients completed a total of 37 neuromodulator trials. Gabapentin demonstrated statistically significant improvement in LCQ scores at 2 months (2.48 points, P≤ .01) and 6 months (5.40 points, P = .01) of treatment as compared with baseline. Patients taking TCAs demonstrated statistically significant improvement of LCQ scores at 2 months of treatment (3.46 points, P≤ .01). However, the majority of patients discontinued treatment, most commonly secondary to the development of tachyphylaxis after 2 months, precluding analysis at 6 months. Conclusion While both neuromodulator classes demonstrated short-term benefit, the majority of patients discontinue treatment prior to 6 months, with patients taking TCAs discontinuing more frequently than patients on gabapentin. Future investigations are warranted evaluating tachyphylaxis and the utility of dual treatment therapies designed to address peripheral and central sensory pathways involved in UCC.
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Affiliation(s)
- Andrew Jay Bowen
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio, USA
| | - Amy S. Nowacki
- Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | - Kevin Contrera
- Cleveland Clinic Head and Neck Institute, Cleveland, Ohio, USA
| | - Douglas Trask
- Cleveland Clinic Head and Neck Institute, Cleveland, Ohio, USA
| | - James Kaltenbach
- Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | | | - Michelle Adessa
- Cleveland Clinic Head and Neck Institute, Cleveland, Ohio, USA
| | | | | | - Paul C. Bryson
- Cleveland Clinic Head and Neck Institute, Cleveland, Ohio, USA
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Sanna MD, Mello T, Masini E, Galeotti N. Activation of ERK/CREB pathway in noradrenergic neurons contributes to hypernociceptive phenotype in H4 receptor knockout mice after nerve injury. Neuropharmacology 2018; 128:340-350. [DOI: 10.1016/j.neuropharm.2017.10.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 12/27/2022]
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Descending Noradrenergic Inhibition: An Important Mechanism of Gabapentin Analgesia in Neuropathic Pain. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1099:93-100. [DOI: 10.1007/978-981-13-1756-9_8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Drugs to Alter Extracellular Concentration of Glutamate: Modulators of Glutamate Uptake Systems. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/978-1-4939-7228-9_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Taylor BK, Westlund KN. The noradrenergic locus coeruleus as a chronic pain generator. J Neurosci Res 2016; 95:1336-1346. [PMID: 27685982 DOI: 10.1002/jnr.23956] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/25/2016] [Accepted: 09/07/2016] [Indexed: 12/17/2022]
Abstract
Central noradrenergic centers such as the locus coeruleus (LC) are traditionally viewed as pain inhibitory; however, complex interactions among brainstem pathways and their receptors modulate both inhibition and facilitation of pain. In addition to the well-described role of descending pontospinal pathways that inhibit spinal nociceptive transmission, an emerging body of research now indicates that noradrenergic neurons in the LC and their terminals in the dorsal reticular nucleus (DRt), medial prefrontal cortex (mPFC), spinal dorsal horn, and spinal trigeminal nucleus caudalis participate in the development and maintenance of allodynia and hyperalgesia after nerve injury. With time after injury, we argue that the balance of LC function shifts from pain inhibition to pain facilitation. Thus, the pain-inhibitory actions of antidepressant drugs achieved with elevated noradrenaline concentrations in the dorsal horn may be countered or even superseded by simultaneous activation of supraspinal facilitating systems dependent on α1 -adrenoreceptors in the DRt and mPFC as well as α2 -adrenoreceptors in the LC. Indeed, these opposing actions may account in part for the limited treatment efficacy of tricyclic antidepressants and noradrenaline reuptake inhibitors such as duloxetine for the treatment of chronic pain. We propose that the traditional view of the LC as a pain-inhibitory structure be modified to account for its capacity as a pain facilitator. Future studies are needed to determine the neurobiology of ascending and descending pathways and the pharmacology of receptors underlying LC-mediated pain inhibition and facilitation. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Bradley K Taylor
- Department of Physiology, School of Medicine, University of Kentucky Medical Center, Lexington, Kentucky
| | - Karin N Westlund
- Department of Physiology, School of Medicine, University of Kentucky Medical Center, Lexington, Kentucky
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